1. Field of the Invention
The field of the present invention is hydraulic braking pressure control systems of the type having an auxiliary hydraulic pressure generating means capable of generating a hydraulic pressure in accordance with the braking operation of a brake pedal, and a hydraulic pressure supply source hydraulic pressure control means interposed between a hydraulic pressure supply source and brake devices for controlling the hydraulic pressure from the hydraulic pressure supply source in accordance with the braking operation of the brake pedal.
2. Description of the Prior Art
Such hydraulic braking pressure control systems are conventionally known, for example, from Japanese Patent Publication Kokoku No. 187/77.
The prior art system controls the braking pressure for the brake devices by the supply source hydraulic pressure control means. However, if the hydraulic pressure supply source is in malfunction or failure for any reasons, so that a sufficient hydraulic pressure from the hydraulic pressure supply source cannot be insured, then it is difficult to provide a sufficient braking pressure to the brake devices.